Just finished this book. I liked it very much, once I got used to the Korean names and a few vocabulary words. This obviously won't bother the Koreans among us, but for the rest of us, there's actually a glossary in the back that might have been helpful if I'd known it was there! But only a little; it wasn't really an obstacle.
The story was exciting, suspenseful, and full of plot twists and surprises. Addressed questions of love and loss, broken families and reunifications. And of course what it means to be raised as a weapon and not as a human girl. This was a well-written, thought-provoking story, well worth the read for that alone.
I'm going to put the ubergirl review inside a spoiler block. If you don't want to read the spoilers, just know that yes, there is ubergirl activity.